Multifunctional restrictive valve

ABSTRACT

A multifunctional restrictive valve for controlling the flow of water therethrough. The valve has a main body with a flow channel through the main body. The main body receives water upstream thereof through an inlet port and passes it out through an outlet port at the downstream end of the body. A flow control assembly is located in the flow channel and includes a temperature sensor/actuator acting on a piston to move, when the temperature sensor heats up the piston, to block water flow control ports. The flow control assembly also includes an override feature wherein the piston is located within a slide and the flow control ports are located in the slide. By moving the slide away from the piston when the piston is blocking the flow control ports, the temperature sensor and piston may be overridden and flow may resume through the main body.

PRIORITY CLAIM

This application is a Continuation of U.S. patent application Ser. No.15/478,065, now U.S. Pat. No. 9,927,402, filed Apr. 3, 2017, which is aContinuation of Continuation of U.S. patent application Ser. No.15/082,950, now U.S. Pat. No. 9,611,629, filed Mar. 28, 2016, which is aContinuation of U.S. patent application Ser. No. 13/857,705, filed Apr.5, 2013, now U.S. Pat. No. 9,309,655, which is a Continuation of U.S.patent application Ser. No. 12/966,471 now U.S. Pat. No. 8,434,693,filed Dec. 13, 2010, which is a Continuation of U.S. patent applicationSer. No. 11/788,884, now U.S. Pat. No. 7,878,417, filed Apr. 23, 2007,which is a Continuation-in-Part of U.S. patent application Ser. No.11/154,404, now U.S. Pat. No. 7,681,804, filed Jun. 15, 2005.

FIELD OF THE INVENTION

The present invention is generally related to restrictive valves, andmore, specifically to controlled fluid flow restrictive valves with atemperature controlled cutoff port, including a resettable releasemechanism for overriding the temperature controlled flow cutoff port.

BACKGROUND OF THE INVENTION

It is often necessary, in both consumer and commercial contexts, to waitfor a water source to reach a suitable temperature prior to use. Forexample, it is very common for an individual to turn on the hot water inthe shower, or at a sink, and then wait for an extended length of timeuntil the water is at the correct temperature.

Additionally, vast amounts of water and energy are wasted each year dueto the delay in receiving water at the correct temperature. That is, asmost individuals are reluctant to stand by the shower and continuouslymonitor the water temperature for many minutes, a significant amount ofhot water is simply lost down the drain. This increases both water costsas well as heating costs. Multiplied by the number of individuals thatmust engage in this practice on a daily basis, the waste is significant.

SUMMARY OF INVENTION

The present invention achieves technical advantages as a temperaturecontrolled valve with manual and hydraulic control features. Oneembodiment of the invention utilizes: a piston adapted to restrict fluidflow through a channel as a function of fluid temperature. A paraffinwax sensor permits unimpeded fluid flow through the channel when thefluid temperature is below a first temperature, reduces fluid flowthrough the channel at a second fluid temperature, and again permitsfluid flow through the channel when the fluid temperature falls belowthe first temperature. Advantageously, the temperature controlled valvehas a release mechanism, typically manually controlled, adapted topermit fluid flow through the channel independent of the fluidtemperature. The release mechanism may be automatically reset as, forexample, by a drop in hydraulic pressure in the valve.

Applicant's novel valve monitors the temperature of the shower water asit warms up. Once the shower water is at an adequate temperature forshowering, the valve pauses or restricts the flow of water in order tosave hot water from going down the drain. When the user is ready for theshower, they reactivate the valve by flipping a lever. This leverbypasses or overrides the temperature activated shutoff mechanism andallows the shower to return to full flow without regard to temperature.Once the user has finished showering, they shut off the water in normalfashion (for example, at the mixing valve). The novel valve devicedetects the shower has been shut off through a drop in hydraulicpressure in the valve and automatically resets itself and arms thebypass for the next use.

Thus, the device is designed to conserve water and energy by reducingthe amount of hot water wasted during the time the person first turns onthe water and when they actually enter the shower (the warm-up period).Applicant's novel valve accomplishes this by restricting or stopping thewater flow from the shower once the water has reached a suitableshowering temperature. However, the user is allowed to resume the flowof water and actually ready to begin using it.

Applicant's valve achieves its novel functions and advantages throughthe use of a water temperature controlled mechanism, including a piston,temperature sensor and water flow ports (for example, in a slide), thatprovides for shutoff when water temperature reaches above apredetermined temperature to avoid wasting hot water. However, the usermay manually engage an override which would allow warm water to flowthrough despite a high temperature condition. With the override engaged,water temperature may be adjusted to suit the user's preference and warmwater, even above the temperature that shutoff the flow from thepre-override position, will continue to flow when the override isengaged or moved from a pre-override position to an engaged or overrideposition. The override is typically activated by the manual unlatchingand the user needs not hold or maintain force on the handle to keep theassembly in the override position. Moreover, Applicant's novel valveincludes means to automatically reset the override to a disengaged orpre-override position wherein the reset is responsive to water pressuredrop (as by mixing valve shutoff, for example).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of the valve assembly.

FIG. 1A is a top elevational view through a section of the valveassembly showing with arrows the water flow.

FIG. 1B is an external side elevational view of the valve assembly.

FIG. 2A is a top sectional elevational view of the valve assemblyshowing with arrows the water flow.

FIG. 2B is an external side elevational view of the valve assembly.

FIG. 3A is a sectional top elevational view of the valve assemblyshowing with arrows the water flow.

FIG. 3B is an external side elevational view of the valve assembly.

FIG. 4 is a sectional elevation side view of the valve assembly.

FIG. 5 is an exploded view of an alternate preferred embodiment of thevalve assembly with some additional and/or different features notillustrated in the previous drawings.

FIG. 5A is a perspective view of the cam used with the valve assembly.

FIG. 5B is a sectional top elevational view of the valve assemblyshowing the override assembly in lockout or disengaged position.

FIG. 5C is a perspective view of the piston used with the valveassembly.

FIG. 6 is an elevational view of the valve assembly integrated with ashowerhead.

FIG. 7 is an illustration of Applicants' valve assembly integrated witha mixing valve or valves.

FIG. 8 is an illustration showing the use of Applicants' valve assemblydownstream of mixing valves.

FIG. 8A is an illustration of Applicants' valve assembly as part of alarger flow control system including a wall.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1-5B, there is shown an exploded view of a firstembodiment of the present invention assembly. The valve assembly 18 iscomprised of the following components: a main body rear 802, a main bodyO-ring 804, a slide spring 806, a slide 808, a slide O-ring 810, apiston spring 812, a piston 814, two piston O-rings 816, a screen 818, abody front 820, an actuator 822, a release pin 830, a release pin spring832, and a pin retention ring 834. The valve assembly housing 12 iscomprised of the following components: a housing first part 824, ahousing second part 826, and a handle 828.

The main body O-ring 804, slide spring 806, and the longer end of theslide 808 are operably, inserted into the wider, threaded end of thebody rear 802. The main body is comprised of body rear 802 and bodyfront 820. The piston spring 812, a first piston O-ring 816, the piston814, and a second piston O-ring 816 are operably inserted into thewider, threaded end of the body rear 802. The screen 818 and the slideO-ring 810 are operably inserted into the wider end of the body front820. The wider, threaded end of the body rear 802 is operably coupled tothe wider end of the body front 820 to enclose the aforementionedcomponents. The temperature sensor and actuator 822 is operably insertedinto the narrower end of the body front 820. The release pin 830 isoperably inserted into body rear 802 with the release pin spring 832.The housing first part 824 and the housing second part 826 are operablycoupled to substantially enclose the valve assembly 18 and the handle828 is operably coupled to the release pin 830. In one exemplaryembodiment, a handle screw 836 is used to operably couple the handle 828with release pin 830.

Body rear 802 further includes main body outlet port 802A, release pinhousing 802B, spring retainer 802D, and stop lip 802C. Slide 808 furtherincludes slide nose 808A, slide head 808B, slide head lower surface808C, hollow slide body 808D, and slide ports 808E for controlling theflow of water through the valve assembly. Piston spring 812 isdimensioned for receipt into hollow slide body 808D and to abut at afront end piston base 814B and at a second end spring retainer 802D.Piston 814 includes piston head 814A, piston base 814B, piston stem814C, and piston head cavity 814D. Piston head 814A includes a pistonhead cavity 814D for receipt of actuator nose 822B there into. Bodyfront 820 includes body end, shoulder 820A capable of receiving andstopping the motion of slide 808 as urged in an upstream direction byslide spring 806. Body front 820 also defines, at an upstream end, inletport 820B. Body front 820 is seen to have threaded walls for threadedengagement with body rear 802. Actuator 822 is seen to have threadedwalls 822A for threaded engagement with threaded walls 820C of bodyfront 820. Actuator 822 also has actuator nose 822B shaped to fit snugwithin piston head cavity 814D as seen in FIG. 1A, for example. FIG. 1Aalso illustrates a channel 814E (see also FIGS. 5B and 5C) throughpiston head 814A, which will allow a small amount of water to flowthrough the valve even when in the shutoff position illustrated in FIG.2A.

FIGS. 1, 1A, and 1B illustrate valve assembly 18. FIGS. 1A and 1Billustrate Applicant's novel valve assembly 18 in an open condition(cool water flow through slide ports 808E illustrated by arrows) andwith the override locked out or disengaged. In the condition illustratedin FIGS. 1A and 1B, an increase in water temperature above apredetermined level will cause piston 814 to move to the right asindicated in FIG. 2A, the piston moving within slide 808, so as to shutoff fluid flow through slide ports 808E when piston head 814A has movedfar enough, that is, to the position as illustrated in FIG. 2A.

Left in the condition as illustrated in FIG. 2A, that is, with overridelocked out or disengaged, the only way water will resume flow issubsequent cooling (allowing hose to retract) which will allow pistonspring 812 to move piston 814 and uncover slide ports 808E, allowingflow to resume through the hollow section of slide body 808D and piston814, and out through outlet port 802A and body rear 802.

FIGS. 3A and 3B illustrate the novel valve assembly 18 after the userhas elected to manually rotate handle 828, so as to withdraw release pin830 from the rear of slide head 808B. Upon movement of the handle asseen in FIGS. 3A and 3B, the movement of slide 808 under the impetus ofwater pressure upstream of slide head 808B will overcome the pressureexerted by slide spring 806 and move the slide downstream and againstannular stop lip 802C in body rear 802. This movement will uncover slideports 808E and allow water (as well as water above the cutofftemperature) to resume flow through hollow sections of piston 814 andslide 808 and out outlet port 802A.

The user can adjust the water mix to the desired temperature above orbelow the cutoff temperature when in the bypass engaged conditionillustrated in FIGS. 3A and 3B. When the user is through with showering,the user will simply shut off the mixing valves which are typicallyupstream of valve assembly 18. At this point (no/low water flow), slidespring 806 will allow slide 808 to move to the left or “upstream,” Whenslide head 808B abuts shoulder 820A, release pin 830 under the impetusof release pin spring 832 will move to the lockout position asillustrated in FIGS. 1A and 1B, thus automatically resetting theoverride to a pre-override position. While the drop in hydraulicpressure allows the slide to move up to the pre-override position, othermechanical or electrical means may be used to achieve this function,including direct mechanical engagement with the mixing valves orposition/pressure sensors combined with actuators to move the slide.

FIGS. 5 and 5B illustrate an additional embodiment of the device as setforth herein which has some additional and/or different features.Further, FIG. 5, given that it is a cross-sectional perspective view,will help further illustrate the structure of some of the elements ofthe invention shown in the earlier Figures.

FIG. 5 illustrates the manner in which body front 820 includes threadedwalls 820C, which allow secure engagement with actuator 822. Screen 818may be sandwiched between body 820 and main body rear 802 to provide forfiltering of water passing through the valve assembly.

Whereas, FIG. 1 illustrates a pair of O-rings 816 fitted by compressionto grooves in outer walls of piston 814, it is seen with respect toFIGS. 5 and 5C that a piston gland O-ring 710 may be provided fitable toa groove on the inner walls of piston head 814A. Gland O-ring 710 willmake contact with the actuator nose 822B as seen in FIG. 5B. Thus, it isseen the embodiment illustrated in FIGS. 5 and 5C has a piston withthree O-rings, two on the outside and one gland O-ring on the inside tocontact the actuator. The two on the outside will be maintained in theirgroove under compression and will contact the inner walls of the slideas seen in FIGS. 1, 1A, and 5B, for example.

The use of the gland O-ring 710 is to help seal off water, the use ofthe three O-rings, including the ones at the ends of the piston, willhelp provide a “cushion” and a “drag” that will provide dampening andthus help reduce the likelihood from “hammering” that may occur.

Details of a release assembly, whose function it is to release slide 808and therefore activate the bypass or override function as seen in FIGS.3A and 3B are seen to include: handle screw 836 for engaging handle 828and extending therethrough to engage release pin threaded portion 830Cof release pin 830. Pin cylinder cap 700, having cap threaded area 700A,screws into a threaded area on release pin housing 802B of body rear802. With this, it can be seen that the release pin spring 832 will acton release pin land 830B. Thus, in the valve assembly, a release pinactuated by a handle, the release pin having cam pin 831, will alwaysurge release pin 830 towards an engaged or interference position asillustrated in FIGS. 5 and 5B. It is seen that release spin 830 has ahole 830D in release pin arm 830A to receive cam pin 831 (shown in FIG.5B) and would be perpendicular to release pin arm 830A and extendthrough the hole 830B. As seen in FIGS. 5 and 5A, cam 706 is insertableinto release pin housing 802B and has boss 706A that will seat into thehole 802G slots in the base of release pin housing 802B. Central opening706C in cam 706 is dimensioned to allow arm 830A to extend through thecam and through opening 802E in the base of release pin housing 820B, soas to be capable of reaching the position which locks out the override(FIGS. 1A, 2A, and 5B).

FIGS. 5, 5A, and 5B also illustrate curved portion 706B of cam 706,which allows cam pin 831 to ride up the curved portion against pressureof release pin spring 832 when the handle is rotated. Riding up from theposition seen in FIG. 5B will allow release pin arm 830A to withdrawfrom the interference or lockout position, and “release” to allow theoverride or bypass to engage. Note that even in position with theoverride engaged (FIG. 3A), release spring 832 is urging release pin armagainst the outside walls of slide head 808B, so as soon as the slidemoves forward (responsive to the mixing valves being shut off, forexample), the release pin arm 830A will automatically engage the rear ofthe slide head 808B (FIGS. 1A, 2A, and 5B) to lock out the override.

FIG. 5B illustrates an embodiment of piston 814 with, two small channels814E and 814F in piston head 814A that will allow water, to tricklethrough the valve even when it is in an off position. This will helpprevent cross-flow on worn mixing valves and acts as a hydraulicdampener to prevent “hammering.” It is seen from FIG. 5B that, if thepiston moved to a port flow blocking position, channels 814E and 814Fwould provide for the trickle flow of water through the valves. Further,the effect of gland O-ring 710 against the actuator nose combined withthe two small channels 814E and 814F provides a “piston pump” hydraulicaction to help prevent by dampening to potential hammering. The pistonbase 814B helps stabilize the piston in the slide and also helps preventhammering.

FIG. 5 also illustrates the use of a flaw restrictor 714 here designedto limit the flow to about 2.5 gallons per minute under typical,pressures, as may be found in valves when the mixing valves are open andthe valve is allowing water to flow therethrough. The position of theflow restrictor is, typically downstream of the main body and thecontrol elements of the valve.

FIG. 5 is also seen to include a ball 716 for engagement with main bodyrear 802 with, for example, the use of threads. Ball 716 will allowrotation with elements downstream thereof, for example, as set forth inFIG. 5B.

FIG. 6 shows valve assembly 18 with ball 716 on the upstream end andattached to body front 820 by threadable means. Thus, ball 716 may beutilized on either the upstream or downstream end of the body.

FIG. 6 also illustrates the use of the valve inside a custom showerhead42. In this embodiment, housing parts 824/826 may be omitted. The valve,except the handle, may be enclosed within the body of the showerhead,forming an integrated showerhead/valve unit.

FIGS. 7 and 8 illustrate the use of Applicants' novel valve assembly 18in a larger environment as part of a water flow control system. FIG. 7illustrates that the novel valve assembly 18 may be physicallyincorporated into the same housing as the mixing valves or valves 72.Mixing valve 72 would typically receive water from a hot water conduit74 and a cold water conduit 76. Integrated within the same assemblyhousing as mixing valves which control the amount of hot and cold watercoming into a single delivery conduit 78, may be the restrictive valveassembly 18.

On the other hand, as seen in FIG. 8, Applicants' valve assembly 18 maybe downstream from mixing valve 72 and in line with a delivery conduit78. In FIG. 8, it is seen that valve assembly 18 is downstream of amixing valve and upstream of a showerhead (not shown).

FIG. 8A illustrates Applicants' novel valve assembly 18 in a largerenvironment as part of a water flow control system. FIG. 8A illustrateshat Applicants may provide a wall 882 to substantially isolate, from theuser and the environment in which the user will bathe, elementsincluding mixing valve 72 excepting handle, which would be exposedthrough wall 882 for manual manipulation by the user. Mixing valve orvalves 72 are known in the art for receiving water from cold, waterconduit 76 and hot water conduit 74. Applicants' water flow controlsystem may include a diverter valve 884 downstream, typically, of valveassembly 18 to, for example, divert water from a showerhead flow or atub faucet flow.

The embodiments illustrated (see, for example, FIGS. 1 and 5), show thatApplicants' temperature sensing mechanism, for example, actuator 822, isadvantageously, but not necessarily, placed in the most upstreamposition so a to better respond to temperature changes and avoid theheat sink effect of elements downstream of the actuator. Further, it isseen that Applicants' sensor is pushing the piston in a downstreamdirection as it expands, that is, pushing in a direction that isassisted by the water pressure, moving the piston, as illustrated in thedrawings from left to right. Actuator 822 is, in one embodiment, a waxactuator adapted to respond by expanding in a range of approximately 90°F. to 110° F., such as an actuator manufactured by Vernet as Model Nos.A034 and A092/P. Element 822 both senses temperature changes andresponds, as by expanding or contracting to such change. The sensing andactuating functions may be achieved through separate elements however.Other temperature actuators/sensors, such as a temperature responsivememory wire, a bimetallic element, or other known and appropriatetemperature responsive phase change materials, or electromechanicallyoperated temperature sensors may be used in conjunction with Applicants'novel valve assembly, such as those known in the art.

As seen with reference to the Figures, the slide will typically have anupstream slide head area that is responsive to water pressure in urgingthe slide to a downstream direction. Likewise, the piston typicallywould have an area exposed to water pressure upstream that would tend tomove it to a downstream position. In Applicants' novel valve, such areaon the slide here seen to be an annular ring, is significantly largerthan the piston head area.

While the grasping member to the release of the override feature isillustrated to be a handle, the override feature may be actuated with alanyard, chain, electronic button, switch and optical or other sensor.Moreover, a visual/audible indicator 829 (see FIG. 8A) may be used toindicate that the shower is ready (that is, when the temperatureactuator has restricted the flow of water). Indeed, a visual or audible“reminder” may be used, including a popout indicator or a constant orblinking light. Temperature or pressure actuated visible or audioindicators may also be used.

FIGS. 1 and 5B illustrate the use of a gland O-ring 804 situated andengaged with the body walls near the downstream end of slide 808 whenthe slide is in its upstream most position. O-ring 810 is seen to engagethe slide head. The use of a gland O-ring will “swipe” the slide alongwith its position at the downstream end of the slide helps, among otherthings, decrease mineral deposits buildup on the slide. O-ring 810 willswipe the channel walls of the body when the slide moves. The use of theO-rings in these positions helps prevent drying out which tends tocreate scale and scale tends to impede the proper effective operation ofthe elements. Between these O-rings, a lubricant, such as a siliconbased lubricant, is provided to keep the channel and slide wallslubricated.

As is illustrated, Applicants' novel valve may be located in between theshower arm and the showerhead using matching threads. It may also beincorporated into the showerhead. Applicants' novel valve assembly maybe retrofitable to many shower arms by removing existing threadedshowerheads and inserting in the space between the showerhead and theend of the shower arm, Applicants' novel valve and threading theshowerhead to the downstream end after threading the valve into the endof the threaded end of the shower arm. The valve may also be built intothe shower arm or shower stall/tub walls (see FIG. 8A).

Although the invention has been described with reference to specific,embodiments, this description is not meant to be construed in a limitedsense. Various modifications of the disclosed embodiments, as well asalternative embodiments of the inventions, will become apparent topersons skilled in the art upon the reference to the description of theinvention. It is, therefore, contemplated that the appended claims willcover such modifications that fall within the scope of the invention.

The invention claimed is:
 1. A valve for controlling a flow of water,the valve comprising: a main body including a channel extending throughthe main body, the channel configured to receive water at an inlet portand pass water to an outlet port so that the inlet port is upstream ofthe outlet port and the outlet port is downstream of the inlet port inrelation to water flow through the channel; and a flow control assemblydisposed in the channel, the flow control assembly including: atemperature sensor configured to sense a temperature of water flowingthrough the channel; a slide biased toward upstream and a piston withinthe slide, the piston also biased toward upstream separate from theslide, the slide and piston are operatively coupled together to controla flow of water in the channel responsive to the temperature sensor, theslide slidably movable between a slide upstream position and a slidedownstream position, wherein when the slide is in the slide upstreamposition, the slide and piston cooperate to allow the flow of waterthrough the channel as a function of the temperature sensor moving thepiston between a piston upstream position and a piston downstreamposition, wherein when the slide is in the slide upstream position andthe piston is in the piston upstream position, the flow of water isrestricted from flowing in the channel, wherein when the slide is in theslide upstream position and the piston is in the piston downstreamposition, the slide and the piston cooperate to allow the flow of waterthrough the channel, wherein when the slide is in the slide downstreamposition, the slide and the piston cooperate to allow the flow of waterthrough the channel regardless of the temperature sensor and the pistonposition; and a rotatable handle operably coupled to a release pin, therelease pin having an extended position and a retracted position,wherein the release pin securely sets the slide in the slide upstreamposition in the extended position, the handle configured to move therelease pin from the extended position to the retracted position topermit the slide, normally biased toward the slide upstream position, tomove to the slide downstream position in response to water pressurewithin the channel.
 2. The valve as specified in claim 1, wherein therotatable handle is configured to allow water to flow in the channelregardless of the temperature of water flowing through the channel.
 3. Adevice for controlling a flow of water, the device comprising: a mainbody including a channel extending through the main body, the channelconfigured to receive water at an inlet port and pass water to an outletport so that the inlet port is upstream of the outlet port and theoutlet port is downstream of the inlet port in relation to water flowthrough the channel; a temperature sensor configured to sense atemperature of water flowing through the channel; a valve comprising aslide and a piston within and separately movable from the slide, thevalve configured to control a flow of water in the channel responsive tothe temperature sensor actuating the piston, the slide movable between aslide upstream position and a slide downstream position, wherein whenthe slide is in the slide upstream position, the valve is configured toallow the flow of water through the channel as a function of the pistonbeing in a piston upstream position or the piston being in a pistondownstream position responsive to the temperature sensor, wherein whenthe slide is in the slide upstream position and the piston is in thepiston upstream position, the flow of water is restricted from flowingin the channel, wherein when the slide is in the slide upstream positionand the piston is in the piston downstream position, the slide and thepiston cooperate to allow flow of water through the channel, whereinwhen the slide is in the slide downstream position, the slide and thepiston cooperate to allow the flow of water through the channelregardless of the piston position; and a handle operably coupled to arelease pin, the release pin having an extended position and a retractedposition, wherein the release pin securely sets the slide in the slideupstream position in the extended position, the handle configured tomove the release pin from the extended position to the retractedposition to permit the slide to move to the slide downstream position inresponse to water pressure within the channel.
 4. The device asspecified in claim 3, wherein the rotatable handle is configured toallow water to flow in the channel regardless of the temperature ofwater flowing through the channel.
 5. The valve as specified in claim 1,wherein the temperature sensor is configured to move the piston to thepiston downstream position when the temperature sensor senses atemperature above a predetermined temperature.
 6. The valve as specifiedin claim 1, wherein the slide is biased toward the slide upstreamposition by a first coil spring.
 7. The valve as specified in claim 6,wherein the piston is biased toward the piston upstream position by asecond coil spring.
 8. The valve as specified in claim 7, wherein thesecond coil spring is nested within the first coil spring.
 9. The valveas specified in claim 1, wherein the flow control assembly is threadedlycoupled into the channel.
 10. The valve as specified in claim 1, whereinas the rotatable handle rotates, the rotatable handle further ridesagainst a curved portion of a cam against pressure of a release pinspring that biases the release pin toward the extended position.
 11. Thevalve as specified in claim 9, wherein the release pin spring isconfigured to bias the release pin into engagement with the slide whenthe slide is in the slide upstream position.
 12. The valve as specifiedin claim 3, wherein the temperature sensor is configured to move thepiston to the piston downstream position when the temperature sensorsenses a temperature above a predetermined temperature.